During the manufacture of many consumer products, such as absorbent articles like diapers, catamenials and the like, there is a need during the manufacturing process to stretch elastic webs of material in the cross-machine direction while the web is being conveyed in the machine direction. Often times there is also a need to stretch these materials during one step of the manufacturing process and then allow these materials to return to their natural un-tensioned state by releasing the stretching forces. Such is the case when creating loop fastening means for refastenable fastening devices as described in commonly assigned and concurrently filed U.S. patent application Ser. No. 08/254,814, P&G case 5294, titled "NONWOVEN FEMALE COMPONENT FOR REFASTENABLE FASTENING DEVICE AND METHOD OF MAKING THE SAME" filed on Jun. 6, 1994 in the names of Allen et al., the disclosure of which is hereby incorporated herein by reference.
In the past, webs of material were stretched while they were being conveyed through the use of tentering equipment. Tentering equipment usually consists of a series of spring loaded clamps attached to a pair of opposing carrier chains. These chains are adjustable in width to provide a desired amount of stretch so as to increase the width of the material. However, these clamps are discrete and discontinuous and produce high stresses in the web material adjacent to the clamping area. This would often cause the web material to rip or tear during the manufacturing process.
In addition, there has been conveying machines for conveying webs of material which would grip the outer edges of the web. An example of such an apparatus that uses what is referred to in the art as a V-Belt is shown in U.S. Pat. No. 4,943,340 issued to Ujimoto et al. on Jul. 4, 1990 and is hereby incorporated herein by reference. V-belts, such as the one disclosed in the herein incorporated reference, use two pairs of belts having V-shaped cross-sections wherein the flat part of the belts make contact with the web of material in order to convey it. However, this type of apparatus will not adequately stretch webs in the cross-machine direction because the belts do not provide sufficient gripping force to hold onto the web. Consequently, the web of material would have a tendency to slip off of the belts resulting in costly shut down time.
There has therefore been a desire to provide an apparatus which can convey a web and continuously stretch the web in the cross-machine direction while it is being conveyed, without the use of clamps, adhesives or the like. There has also been a desire to use such an apparatus to continuously decrease the width of a stretched web so as to remove the stretching forces therefrom.